The invention concerns a lock device. If the key that fits the cylinder core is fully inserted and then turned, rotation of the cylinder core is transmitted to an output element, which performs the desired functions in the vehicle, e.g., the locking or unlocking of a lock. In this case, the free-turning sleeve that rotatably supports the cylinder core is secured by a catch element; the “normal case” of the lock device is then present.
In the event of a forced rotation of the cylinder core by the use of lock-picking tools, the catch element releases the free-turning sleeve. The free-turning sleeve then turns in the housing together with the cylinder core connected by the tumblers without causing the output element to rotate in the housing. The “overload case” is then present. No functions in the vehicle are triggered.
DE 199 59 833 C1 discloses a lock device. In that case, the catch element is seated in a radial opening in the housing. In the vicinity of this radial opening, the housing has a circumferential groove, in which an annular spring is mounted. The annular spring, which is designed as a spiral coil and has several windings, encircles the circumference of the housing and exerts radial spring tension on the catch element. As a result, the catch element tries to hold the free-turning sleeve in a nonrotating position in the housing. The catch element and the annular spring consist of two separate parts, which must be separately produced and mounted. Besides the radial opening for the catch element, it is also necessary to provide the housing with a circumferential groove for the annular spring. During the radial movement of the catch element between the normal case and the overload case, the annular spring expands radially outward, so that this peripheral area of the housing must be kept free and therefore is no longer available for other important components. The annular spring takes up a great deal of space in the peripheral area of the housing.
DE 44 12 609 A1 discloses another lock device, in which a compression spring is mounted in its own chamber of an output element and generates a radial restoring force on a coupling element. The coupling element exerts spring tension on a catch element via axial shoulders, and the catch element rotationally fixes a free-turning sleeve in the housing. This lock device also occupies a great deal of space. Furthermore, the spring element, which operates through the coupling element, is mounted separately from the catch element.